Device for the opening of foil sealed containers

ABSTRACT

Device for opening a sealed container comprising: a knife; means for raising and lowering the knife off the container; rotating means for rotating the knife around the container portion to be cut out; a fixedly positioned jig shaped in the shape of the portion of the container to be cut out; biasing means holding the knife against the jig guide surface to guide the cutting to the desired shape.

United States Patent [191 Jeger et al. 1 June 5, 19 73 [54] DEVICE FORTHE OPENING OF FOIL 1,155,267 9/1915 Peacott ..30/11 1,542,661 6/1925Bradshaw ..30/11 SEALED CONTAINERS 2,554,628 5/1951 Mesik ..30/6.4 [75]Inventors: Hans Jeger; Rudolf Rohre, both of Schaffhausen, SwitzerlandPrimary Examiner-Othell M. Simpson Assistant Examiner-Gary L. Smith [73]Assrgnee: Schwerzerrsche Aluminum AG, Berryv Chippis (VS), Switzerland22] Filed: May 7, 1971 1 1 ABSTRACT [21] App]. No.: 141,312 7 Device foropening a sealed container comprisingz'a knife; means for raising andlowering the knife off the 1 Foreign Application prlol'lty Dalacontainer; rotating means for rotating the knife around the containerportion to be cut out; a fixedly June 5, 1970 Switzerland ..843l/70positioned j g Shaped in the Shape of the portion of the v container tobe cut out; biasing; means holding the [52] US. Cl ..30/6.4, 30/11 knifeagainst the jig guide surface to guide the cutting [5 1] Int. Cl. ..B67b7/30 to the desired shape v [58] Field of Search ..30/6.4, 11,17, 310

[56] References Cited 16 Claims, 3 Drawing; Figures UNITED STATESPATENTS 1,110,334 9/1914 Moran ..30/l1 PATENTEUJUH 5 I975 SHEET 1 BF 3PATENTEDJUH 5197s SHEET 2 [IF 3 0e hm hm NGE DEVICE FOR THE OPENING OFFOIL SEALED CONTAINERS Known semi-automatic openers for tin cans, inparticular for use in canteens, hotels, etc., are not suitable for theopening of foil-sealed lightweight containers, because they undulydeform these and tear them. Such containers, known as lightweightcontainers, are mainly used in the food industry. They consist of abottom section of plastic sheet or aluminum foil or a foil combined fromboth, the aluminum foil being up to 0.20 mm thick, and of a lid of thesame material. The lid foil is joined to a rim flange of the bottomsection by heat sealing. The object of the present invention is toprovide a device for the opening of foilsealed containers.

The device of the invention includes a knife support capable of beinglowered on to the container, means for moving the knife support into itscutting position for cutting the foil along the container rim, a suctiondevice which both holds the foil as it is being cut and, when the knifesupport is lifted after cutting, raises the foil detached from thecontainer.

I The present invention is now to be described by way of example withreference to the accompanying drawings, in which:

FIG. 1 shows a side view partly in longitudinal section, of a device foropening foil-sealed containers of non-round shape;

FIG. 2 shows a top view of the said device, partly in section, alongline II-II in FIG. 1;

FIG. 3 shows another embodiment of a device for opening foil-sealedcontainers, in side view analogous to FIG. 1.

FIGS. 1 and 2 show a device with a baseplate 1 and a lateral support 3for receiving a rod 5. This is provided at its upper end with a knob 6which concurrently serves as an abutment for a spring 7. Rotatablyseated on the rod is a knife support 9, inside which is a jig ll rigidlyjoined to the rod 5. The edge of jig 11 provides a guide surfaceoriented to face in a direction transverse to the container surface tobe opened. The knife support 9 presents two knife holdersl3 and 15.These present guide grooves 17 in which there are two rolls 19. Theserolls support the knife holders 13 and 15 on the edge of the jig ll.Fitted to the knife holders 13 and 15 by bolts 23 are knife bladespresenting I knife-edges 21. The knife holders 13 and 15 are connectedto slides 25 and 29. The slides slide on guide bars 31 and 33, while themiddle section 27 remains fixed. Guide bars 31 and 33 extend generallyparallel to the container surface to be opened. The slides are connectedto the middle section 27 by tension springs 35, 36, 37 and 38 and holder40. A collar 43 rigidly joined to the knife support 9 holds a lever 45with a grip 47.

The baseplate 1 presents a recess 49 for receiving a container 51.Fitted to the lower end of the rod 5 and rigidly joined thereto is asuction cup 53 which, consisting of soft rubber, sits fast when pressedon to a surface.

The device operates as follows:

In the initial position, owing to the pressure of the spring 7, the rod5 together with the knife support 9, the grip 47 and the suction cup 53is in the raised position, so that the container 51 can be easilyslipped into the recess 49 of the baseplate 1. Then, against the actionof the spring 7, pressure is applied to the knob 6 to lower the rod, 5,with the result that the knife-edges 21 penetrate into lid foil 52 ofthe sealed container 51,

and the suction cup 53 is caused to suck itself fast on the foil. Next,the grip 47 is gripped and swung in a plane parallel to the lid foil 52,so that the knife-edges 21 cut through the foil along the container rim55. Where there are two knife blades 20 fitted to knife holders 13 and15 relatively displaced by 180, a swing through slightly more than 180,such as 185, is sufficient to part the foil 52 reliably from thecontainer 51 while preventing any further portions from being cut by theknifeedges 21. When the cut is complete, the grip 47 can be moved backslightly, as through a few degrees, and then the knob 6 can be released.The entire cutting assembly comprising the knife support 9 and thesuction cup 53 with the detached lid returns upwards to its initialposition under the action of the spring 7. The opened container 51 canbe easily removed from the recess 49, as sideways, for instance.

The jig 11 is formed according to the contour of the container rim 55,which may be rectangular with rounded corners, oval, etc. The slides 25and29 are slidably arranged on the guide bars 31, 33. They are subjectto the action of the springs 35-38, ensuring that the knife holders 13and 15 rest against the edge of the jig 11. For smooth action, the knifeholders 13 and 15 are provided with suitable rolls 19 which substitute alargely rolling friction for a sliding friction between jig edge andholders 13 and 15. Balls may be used instead of rolls.

FIG. 3 shows a device analogous to that in FIGS. 1 and 2 for openingfoil-sealed containers. In this embodiment, a base-plate 60 presents adie 61. A support 63 holds an operating lever64 with a grip 66 and aslot 67 by which the lever 64 is action-connected to a guide pin 68 of arod 70. The lever 64 pivots on a pin 69 of the support 63. Continuingthe rod 70 downwards is a piston, shaped component 71 with a dog 73guided in the guide groove 77 of a sleeve 75. The groove of the sleevefitted in the support 63 is formed in such a manner that its upperportion extends parallel to the axis of the rod 70 or thepiston 71.,while its lower portion is bent in the manner shown, so that the dog 73and, with it, the piston 71, which is free to rotate on the rod 70,first performs an axial movement and thereafter, following the bend ofthe groove 77, a combined axial and rotary movement.

Fitted to the piston 71 is a carrier 78 with carrier bars 80. Theseserve to carry along the bolts 82 in the knife holders 84, which carryknife blades 86 with knifeedges 87. The blades are held by bolts 88. Inthis case again, the knife holders 84 are interconnected by springs 89and the carrier 78. The knife holders 84 rest against a jig 91, and thegrooves of the knife holders 84 have rolls 92 or balls intended to guidethe knife holders 84 smoothly along the circumference of the jig 91, Asuction cup 94 is provided as a terminating element. Also shown in FIG.3 is a container 96 to be opened, with a rim 98 and a lid foil 99.

Once the container 96 has been placed in position, with the operatinglever 64 lifted (dashdotted in FIG. 3), this lever is gripped by itsgrip 66 andmoved downwards, with the result that the rod 70 performs astraightline movement, so that the piston 71, being rotatable butaxially fixed in respect thereof, at first also.

performs an axial movement, corresponding to the form of the groove 77.During that movement, the

knife-edges 87 meet the foil 99 and pierce it, whereupon, with the lever64 continuing its downward movement, the piston 71 performs a rotarymovement corresponding to the form of the groove 77, so that theknife-edges 87 move parallel to, or along, the container rim 98 and partthe foil 99 from the rim. According to the number of knife-edges 87, therotary movement performed by the piston 71 is limited to about 95 orabout 185. The suction cup 94, which is pressed against the foil 99 andwhich may be connected to a vacuum device, not shwon, for instance,entrains the detached foil 99, when the lever 64 is lifted, so that,with the lever 64 back in its initial position, the opened container 96is cleared and can be removed from the die 61. Removal may be effectedsideways through a lateral cut-out 95 of the die 61, for instance.

Where the groove 77 has a fully continuous form, the knife support,after the cutting of the foil 99 has been completed, is first lifted andthen swung back into its initial position.

The devices described are designed to open containers of any shape whichare closed with foil such as plastic-backed aluminum foil or the like,in cold condition as well as in hot condition, in such a manner that thedetached foil lid is raised by the device while the container rimremains undamaged. This is an absolute necessity in view of thecontainer stability required. The die for the container and the jig forthe guidance of the knife holders are preferably made as interchangeableparts. The die may consist of plastic or similar material moulded to theshape of the particular type of container.

The suction cup serves not only to lift the detached foil lid, but alsoto keep the lid in position during the opening movement and thus ensurea reliable and neat opening cut.

Instead of having hand lever operation, it is possible to provide theknife support with pneumatic, hydraulic or electrical drive and thusautomate the device yet further.

We claim:

1. Device for opening of sealed containers, comprising:

a knife means;

knife moving means connected with said knife means for moving said knifemeans into cutting engagement with a container and for raising saidknife means off the container, for enabling cutting open of thecontainer;

rotating means connected with said knife means for rotating said knifemeans around the container after said knife means has been moved intoengagement with said container;

holding means for holding a container to be opened fixedly positionedwith respect to said knife means;

a fixedly positioned jig, nonmovably connected with said holding means;said jig including a guide surface facing in a direction transverse tothe surface to be opened of the container;

biasing means for biasing said knife means against said jig guidesurface for guiding said knife means 'as it rotates.

2. The device for opening of claim 1, further comprising ananti-friction bearing interposed between said knife means and said jigguide surface.

3. The device for opening of claim 1, further comprising containercut-out portion engaging means for holding the portion'of the containerto be cut and for lifting out this portion; said container cutoutportion engaging means being connected with to be movable by said knifemoving means.

4. The device of opening of claim 3, wherein said container cutoutportion engaging means is a suction cup.

5. The device for opening of claim 1 wherein said jig guide surface isof a shape to conform to the shape of the container surface beingopened.

6. The device for opening of claim 5, wherein said jig guide surface isnoncircularly shaped.

7. The device for opening of claim 6, wherein said jig is removable andreplaceable with a different said jig having a differently shaped saidguide surface.

8. The device for opening of claim 1, wherein said biasing meanscomprises springs joining said knife means and said rotating means.

9. The device for opening of claim 8, further comprising ananti-friction bearing interposed between said knife means and said jigguide surface.

10. The device for opening of claim 9, further including knife guidebars connected with said rotating means, spaced away from the containersurface to be cut and extending generally parallel to that surface; saidknife means being supported on said guide bars and being shiftabletherealong by said jig and said biasing means.

11 The device for opening of claim 10, wherein said knife moving meanscomprises a shaft which is shifted axially and said rotating meanscomprises a sleeve which is connected with said shaft.

12. The device for opening of claim 11, wherein said knife moving meansshaft extends in the direction of movement of said knife means towardengagement with the container; said rotating means being connected withto be movable with said knife moving means;

a sleeve having an interior through which said rotating means extends;said sleeve being nonmovably secured to said holding means; one of saidrotating means and said sleeve interior has an engageable dog projectingtherefrom; the other of said rotating means and said sleeve interior hasa groove which extends along and which wraps around said sleeveinterior; said dog being engaged in said groove, whereby moving of saidknife moving means causes rotation of said dog and said rotating means.

13. The device for opening of claim 12, wherein said rotating meansincludes a shaft extending up from said rotating means extending intosaid sleeve interior and said dog projects out of the side of saidshaft; said sleeve interior comprises a hollow tube and said groove ison the inside of said tube.

14. The device for opening of claim 1, wherein said knife moving meanscomprises a shaft which is shifted axially and said rotating meanscomprises a sleeve which is connected with said shaft.

15. The device for opening of claim 14, wherein said knife moving meansshaft extends in the direction of movement of said knife means towardengagement with the container; said rotating means being connected withto be movable with said knife;

a sleeve having an interior through which said rotating means extends;said sleeve being nonmovably secured to said holding means; one of saidrotating means and said sleeve interior has an engageable dog projectingtherefrom; the other of said rotating meansand said sleeve interior hasa groove which extends along and which wraps around said sleeve rotatingmeans includes a shaft extending up from said rotating means extendinginto said sleeve interior and said dog projects out of the side of saidshaft; said sleeve interior comprises a hollow tube and said groove ison the inside of said tube.

1. Device for opening of sealed containers, comprising: a knife means;knife moving means connected with said knife means for moving said knifemeans into cutting engagement with a container and for raising saidknife means off the container, for enabling cutting open of thecontainer; rotating means connected with said knife means for rotatingsaid knife means around the container after said knife means has beenmoved into engagement with said container; holding means for holding acontainer to be opened fixedly positioned with respect to said knifemeans; a fixedly positioned jig, nonmovably connected with said holdingmeans; said jig including a guide surface facing in a directiontransverse to the surface to be opened of the container; biasing meansfor biasing said knife means against said jig guide surface for guidingsaid knife means as it rotates.
 2. The device for opening of claim 1,further comprising an anti-friction bearing interposed between saidknife means and said jig guide surface.
 3. The device for opening ofclaim 1, further comprising container cut-out portion engaging means forholding the portion of the container to be cut and for lifting out thisportion; said container cutout portion engaging means being connectedwith to be movable by said knife moving means.
 4. The device of openingof claim 3, wherein said container cutout portion engaging means is asuction cup.
 5. The device for opening of claim 1 wherein said jig guidesurface is of a shape to conform to the shape of the container surfacebeing opened.
 6. The device for opening of claim 5, wherein said jigguide surface is noncircularly shaped.
 7. The device for opening ofclaim 6, wherein said jig is removable and replaceable with a differentsaid jig having a differently shaped said guide surface.
 8. The devicefor opening of claim 1, wherein said biasing means comprises springsjoining said knife means and said rotating means.
 9. The device foropening of claim 8, further comprising an anti-friction bearinginterposed between said knife means and said jig guide surface.
 10. Thedevice fOr opening of claim 9, further including knife guide barsconnected with said rotating means, spaced away from the containersurface to be cut and extending generally parallel to that surface; saidknife means being supported on said guide bars and being shiftabletherealong by said jig and said biasing means.
 11. The device foropening of claim 10, wherein said knife moving means comprises a shaftwhich is shifted axially and said rotating means comprises a sleevewhich is connected with said shaft.
 12. The device for opening of claim11, wherein said knife moving means shaft extends in the direction ofmovement of said knife means toward engagement with the container; saidrotating means being connected with to be movable with said knife movingmeans; a sleeve having an interior through which said rotating meansextends; said sleeve being nonmovably secured to said holding means; oneof said rotating means and said sleeve interior has an engageable dogprojecting therefrom; the other of said rotating means and said sleeveinterior has a groove which extends along and which wraps around saidsleeve interior; said dog being engaged in said groove, whereby movingof said knife moving means causes rotation of said dog and said rotatingmeans.
 13. The device for opening of claim 12, wherein said rotatingmeans includes a shaft extending up from said rotating means extendinginto said sleeve interior and said dog projects out of the side of saidshaft; said sleeve interior comprises a hollow tube and said groove ison the inside of said tube.
 14. The device for opening of claim 1,wherein said knife moving means comprises a shaft which is shiftedaxially and said rotating means comprises a sleeve which is connectedwith said shaft.
 15. The device for opening of claim 14, wherein saidknife moving means shaft extends in the direction of movement of saidknife means toward engagement with the container; said rotating meansbeing connected with to be movable with said knife; a sleeve having aninterior through which said rotating means extends; said sleeve beingnonmovably secured to said holding means; one of said rotating means andsaid sleeve interior has an engageable dog projecting therefrom; theother of said rotating means and said sleeve interior has a groove whichextends along and which wraps around said sleeve interior; said dogbeing engaged in said groove, whereby moving of said knife moving meanscauses rotation of said dog and said rotating means.
 16. The device foropening of claim 15, wherein said rotating means includes a shaftextending up from said rotating means extending into said sleeveinterior and said dog projects out of the side of said shaft; saidsleeve interior comprises a hollow tube and said groove is on the insideof said tube.